• Journal of Microbiology and Biotechnology
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• 제21권12호
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• pp.1330-1335
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• 2011

N-Acyl homoserine lactones (AHLs) serve as the vital quorum-sensing signals that regulate the virulence of the pathogenic bacterium Erwinia carotovora. In the present study, an approach to efficiently restrain the pathogenicity of E. carotovora-induced soft rot disease is described. Bacillus thuringiensis-derived N-acyl homoserine lactonase (AiiA) was projected onto the surface of Pseudomonas putida cells, and inoculation with both strains was challenged. The previously identified N-terminal moiety of the ice nucleation protein, InaQ-N, was applied as the anchoring motif. A surface display cassette with inaQ-N/aiiA was constructed and expressed under the control of a constitutive promoter in P. putida AB92019. Surface localization of the fusion protein was confirmed by Western blot analysis, flow cytometry, and immunofluorescence microscopy. The antagonistic activity of P. putida MB116 expressing InaQ-N/AiiA toward E. carotovora ATCC25270 was evaluated by challenge inoculation in potato slices at different ratios. The results revealed a remarkable suppressing effect on E. carotovora infection. The active component was further analyzed using different cell fractions, and the cell surface-projected fusion protein was found to correspond to the suppressing effect.

• 한국자원식물학회지
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• 제32권6호
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• pp.669-676
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• 2019

Zanthoxylum piperitum D.C. (ZP) peels has been used as a natural spice and herb medicine for hypertension reduction, for strokes, and for its anti-bacterial and anti-oxidant activity. However, the anti-inflammatory mechanisms employed by ZP have yet to be completely understood. In this study, we elucidate the anti-inflammatory mechanism of ZP in lipopolysaccharide (LPS)-induced RAW264.7 cells. We evaluated the effects of ZP in LPS-induced levels of inflammatory cytokines, prostaglandin E₂ (PGE₂), and caspase-1 using ELISA. The expression levels of inflammatory-related genes, including cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS), were assayed by Western blot analysis. We elucidated the effect of ZP on nuclear factor (NF)-κB activation by means of a luciferase activity assay. The findings of this study demonstrated that ZP inhibited the production of inflammatory cytokine and PGE₂ and inhibited the increased levels of COX-2 and iNOS caused by LPS. Additionally, we showed that the anti-inflammatory effect of ZP arises by suppressing the activation of NF-κB and caspase-1 in LPS- induced RAW264.7 cells. These results provide novel insights into the pharmacological actions of ZP as a potential candidate for development of new drugs to treat inflammatory diseases.

• BMB Reports
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• 제49권12호
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• pp.687-692
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• 2016

We recently reported the anti-inflammatory effects of 3-(naphthalen-2-yl(propoxy)methyl)azetidine hydrochloride (KHG26792) on the ATP-induced activation of the NFAT and MAPK pathways through the P2X7 receptor in microglia. To further investigate the underlying mechanism of KHG26792, we studied its protective effects on hypoxia-induced toxicity in microglia. The administration of KHG26792 significantly reduced the hypoxia-induced expression and activity of caspase-3 in BV-2 microglial cells. KHG26792 also reduced hypoxia-induced inducible nitric oxide synthase protein expression, which correlated with reduced nitric oxide accumulation. In addition, KHG26792 attenuated hypoxia-induced protein nitration, reactive oxygen species production, and NADPH oxidase activity. These effects were accompanied by the suppression of hypoxia-induced protein expression of hypoxia-inducible factor 1-alpha and NADPH oxidase-2. Although the clinical relevance of our findings remains to be determined, these data results suggest that KHG26792 prevents hypoxia-induced toxicity by suppressing microglial activation.

• Molecules and Cells
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• 제40권12호
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• pp.925-934
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• 2017

The Cdc6 protein is essential for the initiation of chromosomal replication and functions as a licensing factor to maintain chromosome integrity. During the S and G2 phases of the cell cycle, Cdc6 has been found to inhibit the recruitment of pericentriolar material (PCM) proteins to the centrosome and to suppress centrosome over-duplication. In this report, we analyzed the correlation between these two functions of Cdc6 at the centrosome. Cdc6 depletion increased the population of cells showing centrosome over-duplication and premature centrosome separation; Cdc6 expression reversed these changes. Deletion and fusion experiments revealed that the 18 amino acid residues (197-214) of Cdc6, which were fused to the Cdc6-centrosomal localization signal, suppressed centrosome over-duplication and premature centrosome separation. Cdc6 mutant proteins that showed defective ATP binding or hydrolysis did not exhibit a significant difference in suppressing centrosome over-duplication, compared to the wild type protein. In contrast to the Cdc6-mediated inhibition of PCM protein recruitment to the centrosome, the independence of Cdc6 on its ATPase activity for suppressing centrosome over-duplication, along with the difference between the Cdc6 protein regions participating in the two functions, suggested that Cdc6 controls centrosome duplication in a manner independent of its recruitment of PCM proteins to the centrosome.

• International Journal of Oral Biology
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• 제45권4호
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• pp.218-224
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• 2020

The antitumor effects of octyl gallate (OG) were investigated on FaDu human hypopharyngeal squamous carcinoma cells. At various concentrations, OG inhibited the proliferation of FaDu cells by suppressing cell cycle regulators and induced apoptosis by activating caspase 3 and its downstream poly (ADP-ribose) polymerase, thereby damaging DNA. Immunoblotting demonstrated that OG significantly suppressed the expression of integrin family proteins (integrin α4, αv, β3, β4), hindering cell adhesion. The reduced expression of integrins subsequently mediated the mitogen-activated protein kinase signaling pathway to stimulate the activation of extracellular signal-regulated kinases and c-jun N-terminal kinases, leading to apoptosis. Thus, OG demonstrated antitumor activity on hypopharyngeal squamous carcinoma cells by suppressing cell proliferation and inducing apoptosis.

• 한국미생물·생명공학회지
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• 제40권1호
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• pp.39-42
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• 2012

벼흰잎마름병을 억제하는 물질의 활성을 확인하기 위하여 벼 잎 생엽절편을 이용하는 새로운 스크리닝 방법을 개발하였다. 96 well plate에 잔토모나스 오라이자의 배양액을 분주하고 균등한 크기의 벼 잎 생엽절편을 배치한 후 효능을 확인하고자 하는 물질을 처리하였다. 흰잎마름병균을 억제하는 물질의 활성도는 벼 잎 생엽절편 병징의 면적율로 환산되었다. 물질에 의하여 병의 발생이 억제된 벼 잎 생엽절편은 병원균 배양액 내에서 건전한 녹색을 유지하였고 병이발생된 벼 잎 생엽절편은 황갈색 병징을 나타내었다. 이를 통하여 본 실험법이 빠르고 간편하며, 농도 의존적인 활성확인이 가능하고, 소량으로 다수 물질의 활성 여부를 동시에 평가할 수 있음을 확인하였다. 본 스크리닝 법은 벼흰잎마름병 뿐만 아니라 여타의 수인성 작물질병억제 활성을 확인하는 데 응용 가능성이 있을 것으로 생각된다.

• 동의생리병리학회지
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• 제35권1호
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• pp.15-21
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• 2021

Donggwaja (Benincasae Semen), the seed of Benincasa hispida (Thunb.) Cogn., has been used in Korean traditional medicine to control the body heat and water retention caused by various diseases. Both the symptoms targeted by the herbal medicine in clinic and studies with disease mouse models support the potential anti-inflammatory effect of Donggwaja. However, it is less understood how Donggwaja exerts its possible anti-inflammatory effect. Here, we present evidence that Donggwaja suppresses macrophage inflammatory reactions via expressing tumor necrosis factor a-induced protein 3 (TNFAIP3 or A20) and suppressing NF-kB activity. The ethanol extract of Donggwaja (EED) showed no toxicity when added to RAW 264.7 cells less than 100mg/ml. When treating the cells for 16 h, EED significantly suppressed the nuclear localization of NF-kB, suggesting that EED suppresses NF-kB activity. Concordantly, a semi-quantitative RT-PCR analysis showed that EED decreased the expression of prototypic pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-a, IL(interleukin)-6, and IL-1b. EED induced in RAW 264.7 cells the expression of A20, a ubiquitin modulator that suppresses inflammatory signaling cascades initiated from TLR4 and TNF and IL-1 receptors, while not affecting the induction of Nrf2, an anti-inflammatory factor that could suppress the effect of NF-kB. These results suggest that EED exerts its suppressive effect on inflammation, at least in part, by expressing anti-inflammatory factor A20 and suppressing pro-inflammatory factor NF-kB activity.

• 한국잠사곤충학회지
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• 제51권2호
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• pp.207-210
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• 2013

본 연구는 누에 숙잠 혈림프의 멜라닌 생성 억제 효과에 대해 알아보기 위해 수행되었다. 실샘을 제거한 누에 숙잠에서 혈림프를 정제하였고, 이의 항산화, 멜라닌 생성 억제, 티로시나아제 활성 억제 효과 여부를 실험한 결과는 다음과 같다. 1. 숙잠의 실샘을 제거한 후, 나머지 누에조직을 분쇄하여 원심분리 후 여과하였던 기존의 방식에서 연속식 원심분리로 정제 방법을 개선한 결과, 수율은 53% 증가하였고 정제기간은 5일 단축되었다. 2. 누에 숙잠 혈림프의 DPPH 자유라디칼 소거능을 측정한 결과 비타민 C 보다는 효과가 떨어졌지만 세리신 단일 물질보다 높은 효과를 나타내었다. 3. 숙잠 혈림프 단백질을 음이온 교환 크로마토그래피로 분리하여 활성산소 억제 효과를 측정한 결과, 70 kDa과 30 kDa 단백질이 모두 포함되어 있는 혈림프 단백질(상등액)이 대조군보다 2배, 70 kDa 단백질이 30 kDa 단백질에 비해 약 1.7배 활성산소 억제 효과를 나타냄을 확인하였다. 4. 누에 숙잠 혈림프의 멜라닌 생성 억제 효과는 미백화장품 소재로 널리 사용되는 상백피와 알부틴보다 각각 9.15%, 11.56% 더 우수함을 확인하였다(혈림프 1% 농도 기준). 5. 티로시나아제 활성 억제 효과는 대조인 상백피보다 누에 숙잠 혈림프의 티로시나아제 활성 억제 효과가 우수하였으나 단일 물질인 알부틴보다는 억제 효과가 떨어지는 결과를 나타내었다. 하지만 정제 혈림프 농도 $450{\mu}g/m{\ell}$에서는 90%에 이르는 티로시나아제 활성 억제 효과를 확인하였다.

• 한국식품영양과학회지
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• 제33권6호
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• pp.951-957
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• 2004

한의학에서 당뇨병 (소갈) 처방으로 사용되는 생진양혈탕과 황금탕 처방 성분 중의 하나인 오매의 포도당 이용에 대한 효과를 조사하기 위해서 오매를 70% 에탄올로 추출한 후 메탄올과 물을 섞은 용액으로 단계별로 XAD-4 column으로 분획하였다. 본 연구에서는 3T3-L1 섬유아세포와 지방세포에서 오매의 추출 분획물이 인슐린처럼 작용하는 인슐린성 물질이거나, 인슐린 작용을 향상시키는 인슐린 민감성 물질이거나, 또는 $\alpha$-glucoamylase 활성을 억제하는 물질로 작용하는 지 여부를 조사하였다. 오매 분획물은 인슐린성 물질로 작용하지 않았다. 반면에 20%나 40% 메탄올 분획층은 분화 유도 물질의 작용을 억제하여 3T3-L1 섬유아세포에서 지방세포로의 분화를 억제하였다. 한편 오매 분획층 중 60%, 80% 그리고 100% 메탄올 분획층은 3T3-L1 지방세포에서 인슐린 작용을 향상시키는 인슐린 민감성제로 작용하였다. in vitro 실험에서 20 그리고 40% 메탄올 분획층은 $\alpha$-glucoamylase의 활성을 저하시켜 말토스와 dextrin의 분해를 방해하였다. 그러나 in vivo에서는 오매 에탄올 추출물을 말토스나 dextrin을 투여하기 10분전에 투여하였을 때 최고 혈당 값과 area under the curve 값은 대조군과 차이가 없었다. 결론적으로 오매에는 지방 세포의 분화를 억제하는 물질과 인슐린 민감성을 향상시키는 물질이 함유하고 있으므로 비만을 동반한 당뇨병 및 인슐린 저항성의 치료와 예방에 중요한 역할을 할 것으로 사료된다.

• Journal of Ginseng Research
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• 제24권3호
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• pp.134-137
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• 2000

Spontaneous bursting activity was studied in rat thalamocortical slices using extracellular field potential recording to test the potential utilization of ginsenoside Rb$_1$ in controlling overactivated neural systems. In order to induce bursting activity, slices were perfused with Mg$\^$2+/-free artificial cerebrospinal fluid (ACSF). Two major types of spontaneous bursting activity, simple thalamocortical burst complexes (sTBCs) and complex thalamocortical burst complexes (cTBCs), were recorded in Mg$\^$2+/ -free ACSF. Ginsenoside Rb$_1$ selectively suppressed cTBCs. Duration and occurrence rate of cTBCs were reduced by 87.3${\pm}$10.2% and 85.3${\pm}$ 14.7% in the presence of 90 ${\mu}$M ginsenoside Rb$_1$ respectively, while amplitude and intraburst frequency were slightly changed by ginsenoside Rb$_1$. In contrast, ginsenoside Rb$_1$was much less effective in reducing duration and occurrence rate of sTBCs. We also tested effects of ginsenoside Rb$_1$ on bursting activity in the presence of a GABA$\sub$A/ receptor antagonist, bicuculline methiodide (BMI). Ginsenoside Rb$_1$ had no effect in suppressing BMI-induced bursting activities. These results suggest that ginsenoside Rbi may be useful in controlling seizure-like bursting activity under pathological conditions.